一氧化氮在8-Br-cAMP对视网膜母细胞瘤细胞株影响中的作用

目的研究８－Ｂｒ－ｃＡＭＰ对人视网膜母细胞瘤ＨＸＯ－Ｒｂ４４细胞作用后产生一氧化氮（ＮＯ）的效应,以探讨ＨＸＯ－Ｒｂ４４细胞分化和凋亡的机制。方法应用原位杂交和 ＲＮＡ斑点印迹技术检测 ＮＯＳ ｍＲＮＡ及 Ｂｃｌ－２ ｍＲＮＡ;应用硝酸还原酶法检测ＮＯ的含量;应用蛋白斑点印迹技术检测一氧化氮合成酶（ＮＯＳ）的酶活性;应用免疫细胞化学及蛋白质斑点印迹技术检测 ＮＳＥ的免疫反应性（ＩＲ）。结果 ＮＯＳ ｍＲＮＡ,ＮＯＳ酶活性,ＮＯ含量和 ＮＳＥ－ＩＲ均为实验组（ＥＧ）强于对照组（ＣＧ）（Ｐ＜０．０１）,而Ｂｃｌ－２ ｍＲＮＡ为ＥＧ弱于ＣＧ（Ｐ＜０．０５）,并在ＥＧ标本上可见ＨＸＯ－Ｒｂ４４细胞呈现神经样的突起。结论 ８－Ｂｒ－ｃＡＭＰ可使 ＨＸＯ－Ｒｂ４４细胞生成 ＮＯ增加,促进 ＮＯＳ的酶活性和 ＮＯＳ ｍＲＮＡ的表达,提高ＮＳＥ－ＩＲ,并降低 Ｂｃｌ－２ ｍＲＮＡ的表达。结果表明,８－Ｂｒ－ｃＡＭＰ具有促使 ＨＸＯ－Ｒｂ４４细胞向神经细胞分化并诱导该细胞凋亡的效应,提示ＮＯ可能参与此效应。     

一氧化氮与青光眼

青光眼的发病机制学说不一，近年积累许多证据解释为什么青光眼高眼压已缓解或控制之后，其视野及视神经病变继续恶化。新进展揭示众多分子水平内环境的改变，涉及到视网膜神经节细胞及视神经胶质细胞退行性变性，该过程可能与一氧化氮病理性分泌过多，或微血管内分泌过多；ＥＴ－１分泌过多造成血管内皮机能障碍，缺血再灌注损伤；     

一氧化氮与青光眼

青光眼的发病机制学说不一，近年积累许多证据解释为什么青光眼高眼压已缓解或控制之后，其视野及视神经病变继续恶化。新进展提示众多分子水平内环境的改变，涉及到视网膜神经节细胞及视神经胶质细胞退行性变性，该过程可能与一氧化氮（ＮＯ）病理性分泌过多，或微血管内皮分泌过少；ＥＴ１（内皮素１）分泌过多造成血管内皮机能障碍，缺血再灌注损伤；与兴奋性氨基酸的兴奋性神经毒性；与氧自由基过量；与过氧亚硝酸阴离子诱导的视网膜神经节细胞凋亡有关。     

大鼠视网膜一氧化氮合酶神经元分布及缺血性损伤的改变

目的用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶（ＮＡＤＰＨ）－黄递酶（ＮＤＰ）组化染色法研究大鼠视网膜一氧化氮合酶（ｎｉｔｒｉｃｏｘｉｄｅｓｙｎｔｈａｓｅ，ＮＯＳ）神经元的分布及缺血性损伤ＮＯＳ神经元的变化。方法动物模型采用升高眼内压的方法造成视网膜缺血。摘除眼球后，剥离视网膜，进行ＮＡＤＰＨ－ＮＤＰ反应。结果正常大鼠视网膜ＮＯＳ阳性神经元仅分布于内核层内侧，呈散在分布，具有较长的串株样突起。视网膜缺血１０、３０、６０ｍｉｎ组ＮＯＳ阳性神经元同对照组相比形态学改变及计数均无显著性差异（Ｐ＞０．０５）；而缺血９０ｍｉｎ组，ＮＯＳ阳性神经元数量减少，与对照组相比有显著性差异（Ｐ＜０．０５）。结论正常大鼠视网膜ＮＯＳ阳性神经元散在分布于内核层内侧，可能是无长突细胞；视网膜缺血早期ＮＯＳ阳性神经元无明显变化，提示一氧化氮（ＮＯ）可能不介导ＮＭＤＡ受体激活所致的细胞毒性，缺血晚期数量减少则可能由于ＮＯＳ阳性神经元死亡。     

急性高眼压状态大鼠视网膜一氧化氮 及其合酶变化的研究

目的通过对急性高眼压下大鼠视网膜一氧化氮(nitric oxid e,NO)及其合酶(nitric oxide synthase,NOS)变化的分析,探讨一氧化氮在高眼压视网膜损伤中的作用。方法Wistar大鼠60只,随机分成为高眼压30 min组;高眼压60 min组;高眼压90 min组;高眼压后12 h组和高眼压后24 h 组。前房加压灌注成高眼压模型。利用镀铜镉还原法测定视网膜中NO₂^－/NO₃^－ 的 含量从而间接反映视网膜组织中NO的含量。利用免疫组织化学法研究视网膜内神经结构型一氧化氮合酶(neuronal constitutive nitric oxide synthase,ncNOS)的分布及其变化。结果正常及缺血大鼠视网膜神经结构型一氧化氮合酶(ncNOS)主要位于大鼠视网膜内核层内侧,节细胞层,内丛状层。急性高眼压30min,60min ,90min大鼠视网膜NO的含量逐渐下降(P<0.01),ncNOS阳性 细胞数也逐渐减少(P<0.05),阳性物质表达减弱;急性高眼压 90min后再灌注过程中,NO的含量比90min时明显升高(P<0.05),但与正常比较仍显著下降(P<0.01)。ncNOS阳性细胞数继续减少(P <0.01)。结论一氧化氮参与了急性高 眼压下视网膜损伤过程;通过ncNOS催化的途径合成的NO对缺血以及缺血再灌注的视网膜可能具有重要的作用。(中华眼底病杂志,2001,17:230-233)     

一氧化氮对小肠消化新时期移行性复合运动作用的研究

目的 研究一氧化氮（ＮＯ）在小肠消化间期移行性事运动（ＭＭＣ）控制中的作用。方法在大鼠十二指肠、空肠分别埋置应变片，在动物消醒的动态下分别记录空腹和餐后静脉输液ＮＧ－硝基－Ｌ－精氨酸甲酯（Ｌ－ＮＡＭＥ）、Ｌ－ 氨酸、Ｄ－精氨酸、硝普钠和血管紧张素１后十二指肠、空肠压力变化。结果 在餐后注入一氧化氮合酶抑制剂Ｌ－ＮＭＡＥ，可诱发类似空腹状态下的ＭＭＣ运动形式；注入ＮＯ供体硝普钠，则中断空腹时的小肠Ｍ     

氧化应力对晶状体一氧化氮和一氧化氮合酶活性的影响

探讨氧化应力、５种抗白内障药物对晶状体一氧化氮合酶（ＮＯＳ）活性及一氧化氮（ＮＯ）水平的影响,方法建立晶状体温育模型：培养液分７组：（１）对照组含ＤＭＥＭ １０ｍｌ;（２）－（７）ｘｅｇ ｗｙｎｋＤＭＥＭ１０ｍｌ外尚有３０％Ｈ２Ｏ２０．２ｍｌ,ＦｅＣＬ３２ｍｇ并于（３）－（７）组中分别加入海珠视、麝珠明目、益视安、晶福及视明露滴眼液各１．０ｍｌ,晶状体制备均浆上清,测ＮＯＳ,ＮＯ,ＭＤＡ。结果１．     

Th1、Th17细胞相关因子在实验性自身免疫性葡萄膜炎大鼠中的表达及作用

目的　探讨辅助性Ｔ细胞（Ｔｈｅｌｐｅｒｃｅｌｌｓ,Ｔｈ）１、Ｔｈ１７细胞相关因子在实验性自身免疫性葡萄膜炎（ｅｘｐｅｒｉｍｅｎｔａｌａｕｔｏｉｍｍｕｎｅｕｖｅｉｔｉｓ,ＥＡＵ）中的表达及作用。方法　取清洁级纯系健康雌性Ｌｅｗｉｓ大鼠４０只随机分为ＥＡＵ组（３２只）和对照组（８只）,ＥＡＵ组用光感受器间维生素Ａ类结合蛋白诱导大鼠ＥＡＵ模型,进行临床症状评分,免疫组织化学方法检测造模后视网膜内干扰素（ｉｎｆｅｒｆｅｒｏｎ,ＩＦＮ）-γ、诱导型一氧化氮合酶（ｉｎｄｕｃｉｂｌｅｎｉｔｒｉｃｏｘｉｄｅｓｙｎｔｈａｓｅ,ｉＮＯＳ）、白细胞介素（ｉｎｔｅｒｌｅｕｋｉｎｅ,ＩＬ）-１７、ＩＬ-６的表达。ＥＬＩＳＡ法对比分析房水中各细胞因子的变化情况。结果　ＥＡＵ模型建立成功;造模后第１４天,视网膜损害以外层为主,视网膜内有大量炎细胞浸润,从而导致视网膜内结构紊乱,同时在视网膜的视锥、视杆细胞层和神经节细胞层ｉＮＯＳ、ＩＬ-１７、ＩＬ-６、ＩＦＮ-γ表达,细胞阳性率分别为２９％、４８％、５２％、７３％。在ＥＡＵ发病过程中,ＩＬ-６于造模后第７天迅速升高,第１０天达到高峰;ＩＬ-１７于造模后第１４天达到最高值,变化趋势与炎症进程一致;ＩＦＮ-γ在炎症后期仍有升高,于造模后第１６天达到最高值;ＩＬ-６、ＩＬ-１７、ＩＦＮ-γ与对照组相比,各时间点表达差异均有统计学意义（均为Ｐ＜０．０５）。ｉＮＯＳ在炎症进程中表达有所增加,但与对照组相比,各时间点的表达差异均无统计学意义（均为Ｐ＞０．０５）。结论　Ｔｈ１、Ｔｈ１７细胞相关因子调节网络共同参与实验性自身免疫性葡萄膜炎的发生发展。     

内皮素,一氧化氮在缺氧性肺动脉高压形成中的作用

目的：探讨缺氧性肺动脉高压的形成机制。方法：建立急性缺氧大鼠模型，测定急性缺氧时的平均肺动脉压，血浆内皮素－１（ＥＴ－１）、血清一氧化氮（ＮＯ）、超氧化物歧化酶（ＳＯＤ０丙二醛（ＭＤＡ），及总抗氧化能力（Ｔ－ＡＯＣ）水平。结果急性氧可导致大鼠平均肺动脉压同，同时血浆ＥＴ－１产生增多和ＮＯ合成减少；而血清ＳＯＤ，ＭＤＡ和Ｔ－ＡＯＣ水平则无明显改变。结论：血中ＥＴ－１及ＮＯ水平的变化可能是缺氧性肺动脉     

A MOLECULAR PATHOLOGIC STUDY ON APOPTOSIS IN RETINOBLASTOMA AND THE MECHANISM OF SPONTANEOUS REGERSSION IN RETINOBLASTOMA

ＡＭＯＬＥＣＵＬＡＲＰＡＴＨＯＬＯＧＩＣＳＴＵＤＹＯＮＡＰＯＰＴＯＳＩＳＩＮＲＥＴＩＮＯＢＬＡＳＴＯＭＡＡＮＤＴＨＥＭＥＣＨＡＮＩＳＭＯＦＳＰＯＮＴＡＮＥＯＵＳＲＥＧＥＲＳＳＩＯＮＩＮＲＥＴＩＮＯＢＬＡＳＴＯＭＡＭａｏＪｉａｎ毛健，ＳｕｎＸｉａｎｌｉ...     

Nitric oxide synthase expression in ischemic rat retinas

PURPOSE: To investigate the expression of nitric oxide synthase (NOS) in the ischemic retina. METHODS: Retinal ischemia was induced in rats by bilateral common carotid artery occlusion (BCCAO) for various lengths of time. Using the retina after BCCAO, expression of neuronal NOS (nNOS) and inducible NOS (iNOS) and identification of their positive cells were studied by histological and immunohistochemical examinations. RESULTS: Histological examinations revealed significant reduction in the thickness of the inner plexiform layer and the outer plexiform layer of the retina. Expression of nNOS was detected in retinal ganglion cells, amacrine cells, and Müller cells after BCCAO. The expression of nNOS and iNOS detected in Müller cells became stronger and persisted long after BCCAO. CONCLUSIONS: In the ischemic retina, Müller cells and retinal ganglion cells expressed nNOS and iNOS. These phenomena may be involved in the ischemic damage to the retina.     

倍他洛尔与氨基胍对大鼠视网膜缺血再灌注损伤的保护作用

目的:通过观察在大鼠急性高眼压模型中视网膜一氧化氮合成酶(nitric oxide synthase,NOS)分布及含量的变化,并检测视网膜丙二醛(malondialdehyde,MDA)水平的变化,探讨氨基胍(aminoguanidine,AG)与倍他洛尔(betaxolol)对大鼠高眼压视网膜缺血再灌注损伤的保护作用。方法:采用前房穿刺加压法建立大鼠缺血再灌注损伤模型,维持灌注时间60min。将各组右眼球经视神经矢状切片标本做HE染色进行视网膜组织学观察,还原型尼克酰胺嘌呤二核苷酸磷酸-黄递酶(NADPH-d)法检测视网膜NOS染色阳性的细胞数,硫代巴比妥酸(thiobarbituric acid,TBA)法测定各组左眼球视网膜MDA含量。结果:各组视网膜均有NOS表达,NOS阳性细胞在视网膜主要分布于视网膜节细胞层(ganglion cell layer,GCL)、内丛状层(inner plexiform layer,IPL)、内核层(inner nuclearlayer,INL),200倍视野计数生理盐水组视网膜GCL的NOS阳性细胞数明显高于空白对照组(P<0.01);AG与betaxolol药物治疗各组的NOS阳性细胞数较生理盐水组减少(P<0.05);视网膜NOS阳性细胞数与视网膜MDA含量增减呈正相关性(r=0.69,P<0.01)。结论:AG通过对诱导型NOS的抑制在大鼠高眼压诱导视网膜损伤中起到视神经保护作用。betaxolol通过抑制钙通道,使NO的生成减少,增加抗氧化能力,从而起神经保护作用。     

Expression of neuronal nitric oxide synthase in the retina of a rat model of chronic glaucoma

We investigated the expression of neuronal nitric oxide synthase (nNOS) in a rat retina model of chronic glaucoma, which was produced by electrocauterization of the episcleral vessels. Western-blot analysis showed that nNOS expression was significantly increased in cauterized retinas. nNOS immunoreactivity was observed in the cells of both the inner nuclear layer and the ganglion cell layer. Double labeling of retinal ganglion cells (RGCs) revealed that RGCs in the retina of cauterized rat was nNOS-immunopositive. Systemic administration of L-NAME (N(G)-nitro-L-arginine-methyl-ester), a non-specific NOS inhibitor, reduced RGC loss in cauterized rat retina, but there was no statistical significance (P =.06). These results suggest that the cytotoxicity of excessive NO plays a role in selective RGC loss in glaucoma.     

The contribution of various NOS gene products to HIV-1 coat protein (gp120)-mediated retinal ganglion cell injury

PURPOSE: There is growing evidence that the neuronal pathology seen with HIV-1 is mediated, at least in part, through an excitotoxic/free radical pathway. Nitric oxide (NO) plays a critical role in the nervous system, in both normal and pathologic states, and appears to be involved in a variety of excitotoxic pathways. Whether isoforms of nitric oxide synthase (NOS) are involved in gp120-mediated neuronal loss in the retina was therefore explored. METHODS: To determine which (if any) of the various isoforms of NOS are critical in gp120-mediated damage in the retina, neuronal NOS-deficient [nNOS(-/-)], endothelial NOS-deficient [eNOS(-/ -)], and immunologic NOS-deficient [iNOS(-/-)] mice were subjected to intravitreal injections of gp120. RESULTS: Retinal ganglion cells in the nNOS(-/-) mouse were relatively resistant to gp120, manifesting attenuation of gp120-induced injury compared with wild-type mice. The iNOS(-/-) and eNOS(-/-) mice were as susceptible to gp120 toxicity as control animals. NOS inhibitors were protective against this toxicity. CONCLUSIONS: The presence of nNOS is a prerequisite for the full expression of gp120-mediated loss in the retina; eNOS and iNOS do not appear to play a significant role.     

糖尿病早期NOS亚型的蛋白表达及其在血流变化中作用的实验研究

目的探讨在糖尿病早期,3种亚型一氧化氮合酶(NOS)在大鼠视网膜不同组织细胞中蛋白表达的变化,及其与视网膜血流变化的关系。方法将Wistar大鼠随机分成正常对照组与链脲佐菌素(STZ)腹腔注射诱导的糖尿病组各10只,采用彩色多谱勒对大鼠视网膜中央动脉(CRA)进行血流参数的测量,运用免疫组织化学技术观察视网膜eNOS、iNOS、nNOS蛋白表达的变化。结果8wk糖尿病大鼠视网膜尚未出现病变,但血流参数已显著异常,表现为糖尿病组大鼠CRA的血流速度较对照组显著降低(P<0.05),而阻力指数则显著增高(P<0.05),搏动指数高于对照组,但尚未有显著意义。3种亚型NOS在糖尿病与正常对照组视网膜中表达部位一致;但与正常对照组比较,iNOS免疫反应的强度在糖尿病大鼠视网膜中的内核层显著增强,而eNOS与nNOS的免疫反应强度则未见显著变化。结论在糖尿病早期,大鼠视网膜已开始出现血流灌注不良,此时NOS亚型中iNOS在视网膜中的表达上调可能与之相关。     

Nitric oxide: ocular blood flow, glaucoma, and diabetic retinopathy

Nitric oxide (NO) is widely recognized to be quite an important intercellular messenger in the cardiovascular and nervous systems or immunological reactions, including that in the eye. This molecule formed by constitutive NO synthase (NOS), endothelial (eNOS) and neuronal (nNOS), contributes to physiologically regulate ocular hemodynamics and cell viability and protects vascular endothelial cells and nerve cells or fibers against pathogenic factors associated with glaucoma, ischemia, and diabetes mellitus. Ocular blood flow is regulated by NO derived from the endothelium and efferent nitrergic neurons. Endothelial dysfunction impairs ocular hemodynamics by reducing the bioavailability of NO and increasing the production of reactive oxygen species (ROS). On the other hand, NO formed by inducible NOS (iNOS) expressed under influences of inflammatory mediators evokes neurodegeneration and cell apoptosis, leading to serious ocular diseases. NO over-produced by nNOS in the retina stimulated by excitotoxic amino acids or exposed to ischemia also mediates retinal injury. Because of these dichotomous roles of NO, which has both beneficial and pathogenic actions, one may face difficulties in constructing therapeutic strategies with NO supplementation or NOS inhibition. Up-to-date information concerning physiological roles of NO produced by the different NOS isoforms in the eye and interactions between NO and glaucoma, retinal ischemia, or diabetic retinopathy would help clinicians to select a valid pharmacological therapy that would be appropriate for a specific ocular disease.     

缺血再灌注大鼠视网膜诱导型一氧化氮合酶与细胞凋亡的研究

目的　探讨缺血再灌注大鼠视网膜诱导型一氧化氮合酶 (induciblenitricoxidesynthase ,iNOS)的表达、视网膜细胞凋亡的发生以及二者之间的关系。 方法　采用前房灌注生理盐水的方法制作实验性视网膜缺血再灌注损伤模型 ,分别于再灌注不同时间点取材 ,行免疫组织化学法染色iNOS阳性细胞 ;TUNEL法检测视网膜凋亡细胞 ;透射电镜观察视网膜超微结构。结果　缺血再灌注早期 ,视网膜主要表现为内层水肿增厚 ,晚期主要表现为视网膜萎缩变薄、神经节细胞减少。缺血再灌注 3h组视网膜神经节细胞层及内核层细胞出现iNOS弱阳性表达 ,12h组阳性表达达高峰 ,与其余各组比较差异有显著意义 (P <0 .0 1) ,2 4、4 8h组iNOS表达渐减少。视网膜组织细胞凋亡见于缺血再灌注 12、2 4及 4 8h组 ,凋亡细胞主要位于内核层 ,且 2 4h组凋亡阳性表达最强 ,与其他各组比较差异有显著意义 (P <0 .0 1)。结论　缺血再灌注大鼠视网膜iNOS表达增加 ,介导视网膜缺血再灌注损伤 ;视网膜细胞的损伤部分以凋亡的形式发生 ,iNOS的表达可能对细胞凋亡的发生起一定的诱导作用。     

电刺激大鼠小脑顶核对视网膜缺血再灌注损伤的保护作用

目的　探讨电刺激大鼠小脑顶核对视网膜缺血再灌注损伤的保护作用。方法　大鼠随机分为缺血再灌注组、电刺激组和假手术组。观察视网膜形态学改变 ;用NADPH黄递酶组织化学染色法 (NADPH NDP)观察视网膜内诱导型一氧化氮合酶 (iNOS)的表达 ;采用TUNEL法检测视网膜细胞凋亡情况。结果　 (1)缺血再灌注组的内视网膜层 (包括内核层、内丛状层、节细胞 )、神经纤维层和内界膜厚度增加 ,尤其是内丛状层厚度明显高于假手术组 (t=3 6 80 ,P <0 0 1) ;电刺激组的内视网膜厚度与假手术组相比 ,差异无显著意义 (t=1 0 6 4 ,P >0 0 5 ) ;(2 )光镜观察可见缺血再灌注组有明显的细胞核染色质致密浓缩、核碎裂等改变 ,电刺激组仅见少量核浓缩及碎裂 ;(3)电刺激组的iNOS阳性的神经节细胞数明显低于缺血再灌注组 ,其差异有显著意义 (t=3 32 6 ,P <0 0 1) ;(4)电刺激组大鼠发生凋亡的视网膜细胞数明显低于缺血再灌注组 ,其差异有显著意义 (t=4 0 38,P <0 0 1)。结论　电刺激大鼠小脑顶核对缺血再灌注所导致的视网膜组织损伤具有保护作用。     

大鼠视网膜缺血-再灌注损伤超微结构观察及机制探讨

目的研究大鼠视网膜缺血-再灌注损伤中的超微结构改变以及凋亡相关基因表达的变化,探讨其损伤机制。方法将28只大鼠随机分为正常组和手术组,手术组按照再灌注后不同时间段分为1h、6h、12h、24h、48h、72h组。前房加压法制作大鼠视网膜缺血-再灌注损伤模型,透射电镜检测视网膜超微结构改变,免疫组织化学法检测视网膜组织中bcl-2、bax、Fas的表达。结果(1)正常组视网膜神经纤维中微管及线粒体清晰可见;视网膜神经节细胞(retinal ganglion cells,RGCs)核大,电子密度低,核仁明显,细胞器丰富;再灌注损伤后RGCs核膜肿胀,线粒体嵴模糊不清,可见凋亡小体,神经纤维中微管模糊、减少甚至消失,以再灌注后24h为甚;(2)再灌注后6h,bax表达逐渐递增,24h达到高峰,48h开始下降,72h不明显;(3)bcl-2在视网膜神经节细胞层、纤维层及内核层有微弱表达,各个时间段变化不明显;(4)Fas表达改变与bax基本一致。结论视网膜缺血-再灌注损伤中,细胞凋亡是引起视网膜内核层和神经节细胞层细胞死亡的主要方式,其损伤机制与凋亡相关基因bcl-2、bax、Fas的表达变化有关。     

CNTF and BDNF have similar effects on retinal ganglion cell survival but differential effects on nitric oxide synthase expression soon after optic nerve injury

PURPOSE: To investigate the effect of ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) on retinal ganglion cell (RGC) survival and nitric oxide synthase (NOS) expression in the retina during the early phase of optic nerve (ON) injury, and to examine whether intraperitoneal application of the NOS scavenger nitro-l-arginine (l-NA) could protect the injured RGCs. METHODS: RGCs were retrogradely labeled with granular blue 3 days before the ON was intraorbitally transected. RGC survival was examined 1 week after ON transection and intraocular injection of CNTF and/or BDNF, or 1 to 2 weeks after daily intraperitoneal injection of the NOS inhibitor l-NA. NOS expression was examined by NADPH-diaphorase histochemistry and neuronal NOS (nNOS) immunohistochemistry, and nNOS-positive cells were identified by various staining approaches. RESULTS: Both CNTF and BDNF significantly increased RGC survival 1 week after ON injury. In the ganglion cell layer (GCL), CNTF did not increase the number of NADPH-diaphorase positive ((+)) cells but appeared to reduce the intensity of NADPH-diaphorase staining, whereas BDNF increased the number of NADPH-diaphorase(+) cells and also appeared to enhance the intensity of NADPH-diaphorase staining. In the GCL, amacrine cells but not RGCs were nNOS(+). Some macrophages were also nNOS(+). In contrast, no amacrine cells were nNOS(+) in the inner nuclear layer. Daily intraperitoneal injection of l-NA at appropriate concentrations promoted RGC survival for 1 or 2 weeks after ON injury. CONCLUSIONS: Both CNTF and BDNF protected RGCs after ON injury. CNTF and BDNF acted differently on NOS expression in the GCL. Intraperitoneal injections of l-NA at appropriate dosages enhance RGC survival.